Joshua Robinson of Robinson Design Engineers (RDE) prepares to taste an oyster from Seaborn Oyster Co.’s natural oyster farm at Breach Inlet, SC
With water temperatures at the farm on the rise and average temperatures in Charleston Harbor exceeding 68 degrees, we’ve made the decision to suspend harvesting for the season (South Carolina’s commercial season for wild oysters is scheduled to last until May 15, 2021). We’ll start up again this fall once water temperatures have fallen back down below 70 degrees and the oysters have begun to recover from their season of spawning.
Oysters in the southeast (Crassostrea virginica) begin spawning at around 68 degrees. Oysters prepare for spawning by producing tremendous amounts of gamete. This takes lots of energy—energy that would otherwise be allocated to the production of tissue, glycogen, new shell, etc., components of the oyster that are distinguishable, and often sought-after, in the tasting experience.
This physiological response to warming waters is great for the future prospects of our wild oyster population, but it means the oyster’s flavor gradually degrades through the end of spawning season at which point the animal is left nearly transparent and fully exhausted from a busy summer. It’s then, as waters begin to drop, that the oyster ends its spawning and begins building its energy reserves again. This is when the oyster’s sweetness and ripeness begin to come into season once more.
This natural cycle in which Seaborn operates and by which we are humbly restrained offers clear seasons for us as well. As waters warm and the open season comes to an end, we prepare to support our natural and wild oyster population by planting cultch (i.e. substrate onto which larval stage oysters can land and grow).
This planting season we’re excited to be teaming up with our friends at Robinson Design Engineers to design and deploy a more technical suite of planting strategies that will be customized to the hydrodynamics and geological conditions of our farm. This means we’ll be combining Seaborn’s unique perspective from seasons-worth of experience on the water with RDE’s engineering capabilities using nature-based systems to solve complex problems.
As such, I spent yesterday morning on the water with RDE’s founder and principal Joshua Robinson, scouting site conditions, and talking through several planting solutions in consideration. We expect to finalize our planting design over the next month and anticipate deploying our planting solutions in June.
Engineer Joshua Robinson aboard C/V Marsh Hen II, scouting Seaborn’s oyster beds in preparation for this summer’s planting activity
Joshua Robinson inspects an eroded creek bank adjacent to Seaborn’s site at Breach Inlet. This bank—void of oysters—has eroded from boat wake (primarily) and wind-driven waves that would have otherwise been absorbed by an oyster bed. RDE and Seaborn will be deploying several restorative planting strategies this summer in hopes of stabilizing and renourishing damaged banks while increasing productive growing acreage for oyster cultivation.
Background: An example of the coastal processes and geomorphology associated with natural oyster beds. This bed has grown vertically, encouraging enough sediment accretion over the years such that Spartina grass has colonized the highest ecological niche of this micro island.
Joshua inspects the wave- and energy-dampening abilities of natural oyster beds at Pelican Point. Notice the surface water disturbance on the windward side of the reef versus the leeward side of the reef. At scale, such a perimeter of natural oyster reefs will inherently protect upland resources from damaging storm surge. Unfortunately, many of these natural perimeter protections have been lost along the cost, and municipalities like Charleston are proposing rigid solutions such as walls of concrete to protect their upland resources; man-made systems will typically weaken over time (being strongest the day they’re installed) while natural systems such as a perimeter oyster reef will strengthen over time.